<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      for (;;) {
        let username = prompt('请输入用户名')
        let pwd = +prompt('请输入密码')
        if (username === 'admin' && pwd === 123456) {
          alert('登录成功')
          break
        }
      }
    </script>
  </body>
</html>
